Crow’s Feet: These are lateral canthal lines, also known as crow’s feet or laugh lines. These small lines and wrinkles form from tiny muscles contracting in the outer corner of your eyes as you experience the many different emotions that influence your facial expressions: laughter, stress, grief and sadness.

They usually start out as noticeable lines that form when you smile and your eyes naturally squint. Over time, these fine lines may start to appear on your face when you’re not smiling or even when you’re at rest.

Two proteins that help skin retain its plump, youthful appearance — collagen and elastin — naturally decrease as you age. As these proteins wane, you develop fine lines such as frown lines and crow’s feet.